For instance, the antibiotic rifampicin, a potent and selective activator of human SXR, can up-regulate hepatic metabolism of steroids to the extent that patients were incorrectly diagnosed with Cushing’s syndrome following overnight dexamethasone suppression tests (Kyriazopoulou and Vagenakis 1992). Here, NR1I2 is linked to Cushing syndrome due to macronodular adrenal hyperplasia.